Since 1824, navigation has been one of the earliest missions of the U.S. Army Corps of Engineers (USACE), providing safe, reliable, efficient and environmentally sustainable waterways for movement of commerce, national security needs and recreation across the nation.
But as our nation’s inland navigation network has expanded, so too has the volume of vessels using it. What has also grown is the size of those ships, the wakes they create and the impact those wakes can have and are having on our vital waterways.
Vessel wakes from commercial and recreation crafts are causing disruption to these waterways and are a universal concern for USACE. The wake from vessels causes flooding, coastal erosion, saltwater intrusion, an increased need for dredging and receding shorelines.
“Vessels are becoming longer, wider and deeper, and they push more and more cargo,” said Dr. Matt Malej, a research mathematician with the U.S. Army Engineer Research and Development Center (ERDC). “What that means is that you have waves being generated that are bigger, that are a lot more powerful, and a lot more complex. The waves don’t just come and go away. They ring for literally up to 30 minutes after the vessel has left, and current vessel wake quantification methods are inadequate.”
Authoritative and robust quantification of vessel wake effects has been a missing capability and is a frequent request from USACE districts and other cooperating environmental agencies. Currently, there is no readily available method to quantify impacts caused by ship wakes across different time scales and for all types and classes of vessels.
This absence of a uniform method, as more and larger vessels are being put into service, leads to crude approximations, which prove inaccurate in the long term, resulting in operational and legal challenges.
A solution to this issue lies with FUNWAVE, a numerical wave model that simulates ocean surface wave propagation in shallow and intermediate water. The model, co-developed and put into operation by USACE since 2014, can be used to model complex coastal processes, such as tsunami waves, coastal inundation, wave propagation and surf zone-scale optical properties.
“FUNWAVE can provide operational ship-wake modeling by providing easy access to high-fidelity numerical modeling of ship waves and corresponding shoreline effects for the districts,” Malej said. “It is a collaborative cloud-based model that can quickly test new scenarios and impacts to proposed dredging operations, design of breakwaters and other wave attenuation structures.”
High fidelity modeling such as FUNWAVE can save USACE time, resources and money in planning and pre-construction. The tool can be accessed remotely via a web browser and requires minimal training, which is available through workshops, testbeds, online self-paced video tutorials, publications and a Wiki page.
“The benefit to district engineers using FUNWAVE is unlimited,” Malej said. “Vessels and their wakes will continue to be large, creating issues for commerce and recreation. Using FUNWAVE saves time and money and limits the impact to the environment. It is a win for everyone.”